Association of COVID-19 with obesity Association of COVID-19 with obesity

COVID-19 is a disease that cause respiratory illness due to novel corona virus. It was reported to WHO on December 31,2019 for the first time. The outbreak of this disease started from Wuhan city, China. Now COVID-19 pandemic is spreading worldwide mostly in Europe and North America, these regions have high prevalence of obesity. In the pathogenesis of COVID-19 disease, obesity assumes a significant job. Theinsusceptible framework, which is official in the pathogenesis of COVID19, assumes asignificant job in weight instigated fat tissue aggravation. In the fat tissue the irritationbrings about metabolic brokenness conceivably prompting dyslipidemia, type 2diabetes mellitus, insulin obstruction, hypertension and cardiovascular sickness. Obesity has been expanded the vulnerability to contaminations. In this pandemic, a large number of obese individual with Covid-19 are reported. Infection rate in obese is greater due to poor immunity, comorbidity and inadequate nutritional needs. Statistical analysis showed that about 41.7% patients reported in New York city were obese. Whereas 40% obese have been reported in United State of America with Covid-19. A report from UK indicated that 38% obese were admitted in ICU with Covid-19. According to Chinese researchers, obese individuals are 3-timesmore prone toward the development of Covid-19. So recent analysis indicated that obesity is the major risk factor of Covid-19. In COVID-19, overweight and obese patients have high danger of metabolic difficultiesand eternal infections that stoutness works. More nutrition care is required for such patients. As nutrition is a key factor for keeping up human wellbeing, for example, denseimpervious framework and satisfactory admission of supplements and dietaryenhancements. Tolerant with COVID-19 create contamination from slight to seriousindications bound to the dietary status. Consequently, assessing wholesome status ofindividuals with contamination turns out to be increasingly significant. Through dietaryhelp, we can bring down the danger of oxidative pressure, infection contamination andexpands invulnerability framework among obese people especially.

Geometric Modeling and Characterization of 3-D Land Mobile Radio Cellular Propagation Channels

Accurate knowledge of radio channel characteristics is of immense importance to meet the dynamic requirements of the emerging fifth generation (5G) communication networks. The existing widely used radio channel models are not adequate for the 5G potential candidate technologies because of numerous strong and obvious reasons including very large antenna arrays with high directional resolution (massive MIMO), direct machine-to-machine (M2M) communication links, small sized cells with high users’ density, and less elevated base stations (BS), etc. Among the various channel modelling approaches, the geometrically based channel modelling is a notable method for establishing the probabilistic relationships between spatial locations of transmitter, receiver, and scattering objects. In various indoor and outdoor radio propagation environments, the local vicinity of mobile user terminals is usually a scattering free region. This aspect has been incorporated in various two dimensional (2-D) scattering models available in the literature; however, no three dimensional (3-D) model exists in the literature which is flexible enough to adapt such propagation scenarios. In this thesis, a geometry based 3-D stochastic channel model for land mobile radio cellular propagation environments is proposed, which offers high degree of flexibility in the geometry of scattering volumes to accurately adapt the targeted propagation scenario. The research contributions of this thesis are divided into two main parts, viz: spatial channel model for macro-cellular and M2M (and pico-cellular) radio propagation environments. In the first part, a geometrically based tunable spatial channel model for macrocellular propagation environments is presented. Uniformly distributed scattering objects are assumed around the mobile station (MS) bounded within an ellipsoidal shaped scattering region (SR) hollowed with an elliptically-cylindric scattering free region in immediate vicinity of the MS. To ensure the degree of expected accuracy, the proposed model is designed to be tunable (as required) with nine degrees of freedom, which is unlike its counterparts in the existing literature. The outer and inner boundaries of SR are designed as independently scalable along all the axes and rotatable in horizontal plane around their origins centered at MS. The elevated BS is considered outside the SR at a certain adjustable distance and height w.r.t. position of MS. Closed-form analytical expressions for joint and marginal probability density functions (PDF) of angle-of-arrival (AoA) and time-of-arrival (ToA) are derived for both up- and down-links. Performance of antenna array systems and signal processing techniques implemented at the BS strongly depend on the available knowledge of the radio channel’s characteristics regarding the dispersion of multipath waves in horizontal and vertical planes. Since, the quantification of multipath dispersion in 3-D angular domain is of vital importance for designing large scale planner antenna arrays with very high directional resolution for emerging 5G communications, therefore, a thorough analysis on the multipath shape factors (SF) of the proposed analytical 3-D channel model is conducted. Mobility of user terminal imposes time variability in radio channel’s characteristics. In order to comprehend the mobility of user terminal into the proposed channel model, characterization of Doppler spectrum and second order fading statistics of the radio propagation channel is also presented. Mathematical expressions for joint and marginal PDF of Doppler shift and multipath power are derived. An analysis on the spatial, temporal, Doppler spectrum, and second order fading statistics of the radio channel is presented, where the impact of various physical channel parameters on its statistical characteristics is analyzed. In the second part of the thesis, the proposed channel model for macrocellular environments is extended for small cells and machine to machine (M2M) communication scenarios by considering the effective scattering objects around both ends of the communication link. Using the proposed model, closed-form expressions for the joint PDF of AoA and ToA are derived in azimuth and elevation planes. Similar to the analysis conducted for macrocellular environment in first part of the thesis, a comprehensive analysis on the impact of various input geometric parameters on the spatial and temporal statistics of the channel is presented. In order to evaluate the robustness and establish the validity of the proposed analytical model, a comparison of the proposed analytical results with experimental datasets (available in the open literature) and performed computer simulation results is presented. The proposed analytical results are seen to fit a vast range of empirical datasets taken for various outdoor radio propagation environments. This good agreement in analytical, experimental, and simulation results establishes validity of the proposed model. Moreover, the proposed model is shown to degenerate to various notable geometric channel models in the literature by an appropriate choice of a few parameters.